The refernces we used were:
http://www.vtaide.com/png/George/earthquake.htm
http://www.pdc.org/iweb/volcano_earthquake_relation.jsp?subg=1
http://www.google.com.au/imgres?imgurl=http://www.flixya.com/files-photo/k/u/m/kumareshg1868391.jpg&imgrefurl=http://www.flixya.com/photo/1868391/Volcano-Diagram-Cross-Section&usg=__dfXjkHXiP2l8YNjDLxKxWdJgFHk=&h=500&w=500&sz=51&hl=en&start=8&zoom=1&tbnid=vYgHAPuL2w-bDM:&tbnh=130&tbnw=130&ei=RE68TtvICeX-mAWGx-WkBA&prev=/search%3Fq%3Dvolcano%2Bdiagram%26um%3D1%26hl%3Den%26safe%3Dactive%26sa%3DN%26gbv%3D2%26ie%3DUTF-8%26tbm%3Disch&um=1&itbs=1
http://en.wikipedia.org/wiki/Volcano
http://www.enchantedlearning.com/subjects/volcano/
http://www.infoplease.com/science/weather/japan-tsunami-2011.html
http://www.abc.net.au/news/2011-03-11/tsunami-swamps-japan-after-powerful-quake/2661744
http://www.google.com/imgres?imgurl=http://images.nationalgeographic.com/wpf/media-live/photos/000/317/cache/japan-volcano-kirishima-lightning-3_31752_600x450.jpg&imgrefurl=http://news.nationalgeographic.com/news/2011/01/pictures/110128-james-bond-volcano-eruption-lightning-japan-science-kirishima/&usg=__IDmtoVDe2nw0MG3E-q-hUMJmkO0=&h=426&w=600&sz=49&hl=en&start=8&zoom=1&tbnid=Sv2S4lJK4fhqrM:&tbnh=96&tbnw=135&ei=4vLCTo_lBIWUiQe6_9jjDQ&prev=/search%3Fq%3Dvolcano%2527%26hl%3Den%26safe%3Dactive%26gbv%3D2%26ie%3DUTF-8%26tbm%3Disch&itbs=1
http://www.google.com/imgres?imgurl=http://scijinks.nasa.gov/_media/en/site/volcanic-ash/iceland-volcano-ash-cloud-500.jpg&imgrefurl=http://scijinks.nasa.gov/volcanic-ash&usg=__iN4_gTspsthtXCax-8i_WYPHGHU=&h=333&w=500&sz=17&hl=en&start=6&zoom=1&tbnid=wDmN4pDO99ArxM:&tbnh=87&tbnw=130&ei=CfPCTqSyOIWYmQXJtoWGCw&prev=/search%3Fq%3Dvolcanic%2Bash%26hl%3Den%26safe%3Dactive%26gbv%3D2%26ie%3DUTF-8%26tbm%3Disch&itbs=1
http://en.wikipedia.org/wiki/Volcano
http://www.enchantedlearning.com/subjects/volcano/
http://www.google.com.au/imgres?imgurl=http://www.flixya.com/files-photo/k/u/m/kumareshg1868391.jpg&imgrefurl=http://www.flixya.com/photo/1868391/Volcano-Diagram-Cross-Section&usg=__dfXjkHXiP2l8YNjDLxKxWdJgFHk=&h=500&w=500&sz=51&hl=en&start=8&zoom=1&tbnid=vYgHAPuL2w-bDM:&tbnh=130&tbnw=130&ei=RE68TtvICeX-mAWGx-WkBA&prev=/search%3Fq%3Dvolcano%2Bdiagram%26um%3D1%26hl%3Den%26safe%3Dactive%26sa%3DN%26gbv%3D2%26ie%3DUTF-8%26tbm%3Disch&um=1&itbs=1